Concise review of stereotactic irradiation for pediatric glial neoplasms: Current concepts and future directions

Table 1 Selected series of stereotactic irradiation for low grade glioma including pediatric patients

Ref.	Study period	Number of patients	Proportion of pediatric patients (%)	Histology	Setting	Treatment	Dose (Gy)	Age (yr)	Tumor size	Prior irradiation	Follow-up duration	Tumor control or PFS (%)
Barcia et al[73], 1994	1978-1991	16	50	LGG	Primary or boost therapy	SRS by use of a cobalt source and stereoguide	Mean margin dose 21.7 Gy	Median age 20 yr (range: 4-68 yr)	-	12 patients	Median 50 mo	Tumor control 81
Somaza et al[74], 1996	1990-1993	9	100	Pilocytic astrocytoma	Adjuvant or salvage therapy	GKSRS	Median margin dose 15 Gy	Mean age 8.6 yr (range: 4-17 yr)	Mean tumor diameter 16 mm	2 patients	Median 19 mo	Tumor control 100
Kida et al[75], 2000	2000	12 (total number of patients in the study is 51)	100	WHO Grade I low grade astrocytoma	As part of initial management or salvage therapy	GKSRS	Mean margin dose 12.5 Gy	Mean age 9.8 yr	Mean tumor diameter 25.4 mm	-	Mean 27.6 mo	Tumor control 91.7
Boëthius et al[76], 2002	1978-1997	19	84.2	Pilocytic astrocytoma	Adjuvant therapy	GKSRS	Median margin dose 10 Gy	Mean age 10.6 yr (range: 2-60 yr)	Median 2.2 cc	2 patients	Median radiological follow-up 4.7 yr	Tumor control 94.7
Hadjipanayis et al[77], 2003	1987-2000	49	59	Pilocytic astrocytoma (37 patients) and WHO Grade II fibrillary astrocytoma (12 patients)	As part of initial management or salvage therapy	GKSRS	Median margin dose 15 Gy	Median age 14 yr (range: 3-52 yr) for patients with pilocytic astrocytoma and median age 25 yr (range: 5-57 yr) for patients with WHO Grade II fibrillary astrocytoma	Median 3.3 cc	13 patients	Median 32 mo after SRS	Tumor control 67
Saran et al[78], 2002	1994-1999	14	100	LGG	As part of initial management or salvage therapy	LINAC-based SRT	Total dose 50-55 Gy	Median age 8 yr (range: 5-16 yr)	Median 19.5 cc	0 patient	Median 33 mo	PFS 87 at 3 yr
Marcus et al[79], 2005	1992-1998	50	-	WHO Grade I-II astrocytoma	Salvage therapy	LINAC-based SRT	Mean total dose 52.2 Gy	Median age 9 yr (range: 2-26 yr)	≤ 5 cm in maximal dimension in all patients	0 patient	Median 6.9 yr	PFS 82.5 at 5 yr, PFS 65 at 8 yr
Wang et al[80], 2006	1993-2003	21	-	LGG	Primary, boost, adjuvant or salvage therapy	GKSRS	Median margin dose 14.5 Gy	Median age 20 yr (range: 6-70 yr)	Median 2.4 cc	7 patients	Median radiological follow-up 49 mo	Tumor control 67
Kano et al[81], 2009	1987-2006	50	100	Pilocytic astrocytoma	As part of initial management or salvage therapy	GKSRS	Median margin dose 14.5 Gy	Median age 10.5 yr (range: 4.2-17.9 yr)	Median 2.1 cc	5 patients	Median 55.5 mo	PFS 70.8 at 5 yr
Henderson et al[82], 2009	1997-2004	12	-	WHO Grade I LGG (10 patients), WHO Grade II LGG (2 patients)	As part of initial management or salvage therapy	GKSRS	Median margin dose 13 Gy	Median age 17.4 yr (range: 5.9-63 yr)	Median 4.4 cc	4 patients	Median 48.2 mo	PFS 75 at 4 yr
Weintraub et al[83], 2012	1989-2011	24	100	LGG	As part of initial management or salvage therapy	GKSRS	Median margin dose 15 Gy	Median age 11 yr (range: 4-18 yr)	Mean 2.4 cc	3 patients	Median imaging follow-up 74 mo	Tumor control 83
Hallemeier et al[84], 2012	1992-2005	18	33	Pilocytic astrocytoma	As part of initial management or salvage therapy	GKSRS	Median margin dose 15 Gy	Median age 23 yr (range: 4-56 yr)	Median 9.1 cc	10 patients	Median 8 yr	PFS 41 at 5 yr
Lizarraga et al[85], 2012	1995-2010	12	41.7	Pilocytic astrocytoma	Salvage therapy	LINAC-based SRS or SRT	Median dose 18.75 Gy for SRS and median dose 50.4 Gy for SRT	Median age 21 yr (range: 5-41 yr)	Median 6.5 cc for SRT and median 1.69 cc for SRS	0 patient	Median 37.5 mo	PFS 73.3 at long term
Simonova et al[86], 2016	1992-2002	25	100	Pilocytic astrocytoma	As part of initial management or salvage therapy	GK-based SRS or SRT	Median margin dose 16 Gy for patients receiving single fraction, median dose 25 Gy for SRT	Median age 13 yr (range: 3-17 yr)	Median 2.7 cc	2 patients	Median 15 yr	PFS 80 at 10 yr
Trifiletti et al[87], 2017	1990-2015	28	-	Pilocytic astrocytoma	As part of initial management or salvage therapy	GK-based SRS or SRT	Median margin dose 16 Gy	Median age 17.4 yr (range: 2-70.3 yr)	Median 1.84 cc	4 patients	Median 5.4 yr	PFS 96 at 6 yr
Gagliardi et al[88], 2017	2001-2014	39	23.8	LGG	As part of initial management or salvage therapy	GKSRS	Median margin dose 15 Gy	Median age 31 yr (range: 9-72 yr)	Median 1.24 cc	8 patients	Median 54.5 mo	PFS 52.8 at 5 yr

LGG: Low grade glioma; SRS: Stereotactic radiosurgery; GKSRS: Gamma knife stereotactic radiosurgery; WHO: World Health Organization; PFS: Progression free survival; LINAC: Linear accelerator; SRT: Stereotactic radiotherapy.